| Value | Category | Cases | |
|---|---|---|---|
| 1 | a.No difficulty | 35 |
0.2%
|
| 2 | b.Some difficulty | 18 |
0.1%
|
| 3 | c.A lot of difficulty | 3 |
0%
|
| 4 | d.Cannot do at all | 1 |
0%
|
| Missing value | 23081 |
99.8%
|